Cancer Chemotherapy and Pharmacology最新文献

Background: Drug resistance is one of the major reasons of the poor prognosis and recurs frequently in glioma. Ferroptosis is considered to be a new therapeutic strategy for glioma.

Methods: Microsomal glutathione S-transferase 1 (MGST1) expression in glioma samples was ensured through GAPIA database, qRT-PCR, western blotting assay and immunohistochemistry. The interaction between zinc finger protein 384 (ZNF384) and MGST1 promoter was analyzed through UCSC and JASPAR databases and further verified by ChIP and luciferase reporter assay. Cell viability and IC50 value of temozolomide (TMZ) was measured by CCK-8 assay. The production of MDA, GSH and ROS and the level of Fe²⁺ were determined using the corresponding kit.

Results: MGST1 expression was increased in clinical glioma tissues and glioma cells. MGST1 expression was increased but ferroptosis was suppressed in TMZ-resistant cells when contrasted to parent cells. MGST1 silencing downregulated IC50 value of TMZ and cell viability but facilitated ferroptosis in TMZ-resistant cells and parent glioma cells. Moreover, our data indicated that ZNF384 interacted with MGST1 promoter and facilitated MGST1 expression. ZNF384 was also increased expression in TMZ-resistant cells, and showed a positive correlation with MGST1 expression in clinical level. ZNF384 decreasing enhanced the sensitivity of resistant cells to TMZ, while the effect of ZNF384 could be reversed by overexpression of MGST1.

Conclusion: MGST1 transcription is regulated by transcription factor ZNF384 in TMZ-resistant cells. ZNF384 confers the resistance of glioma cells to TMZ through inhibition of ferroptosis by positively regulating MGST1 expression. The current study may provide some new understand to the mechanism of TMZ resistance in glioma.

Imatinib is the tyrosine kinase inhibitor used as the gold standard for the treatment of Chronic Myeloid Leukemia. However, about 30% of patients do not respond well to this therapy. Variants in drug administration, distribution, metabolism and excretion (ADME) genes play an important role in drug resistance especially in admixed populations. We investigated 129 patients diagnosed with Chronic Myeloid Leukemia treated with imatinib as first choice therapy. The participants of the study are highly admixed, populations that exhibit genetic diversity and complexity due to the contributions of multiple ancestral groups. Thus, the aim of this work was to investigate the association of 30 SNVs in genes related to response to treatment with Imatinibe in CML. Our results indicated that for the rs2290573 of the ULK3 gene, patients with the recessive AA genotype are three times more likely to develop resistance over time (secondary resistance) (p = 0.019, OR = 3.19, IC 95%= 1.21-8.36). Finally, we performed interaction analysis between the investigated variants and found several associations between SNVs and secondary resistance. We concluded that the variant rs2290573 of the ULK3 gene may be relevant for predicting treatment response of CML with imatinib, as well as possible treatment resistance. The use of predictive biomarkers is an important tool for therapeutic choice of patients, improving their quality of life and treatment efficacy.

Background: A clinical drug-drug interaction (DDI) study was designed to evaluate the effect of multiple doses of modafinil, a moderate CYP3A4 inducer at a 400 mg QD dose, on the multiple oral dose pharmacokinetics (PK) of encorafenib and its metabolite, LHY746 and binimetinib and its metabolite, AR00426032.

Methods: This study was conducted in patients with BRAF V600-mutant advanced solid tumors. Treatment of 400 mg QD modafinil was given on Day 15 through Day 21. Encorafenib 450 mg QD and binimetinib 45 mg BID were administered starting on Day 1. PK sampling was conducted from 0 to 8 h on Day 14 and Day 21. Exposure parameters were calculated for each patient by noncompartmental analysis and geometric least-squares mean ratio. Corresponding 90% confidence intervals were calculated to estimate the magnitude of effects.

Results: Among 11 PK evaluable patients, encorafenib C_max and AUC_last were decreased in presence of steady-state modafinil by 20.2% and 23.8%, respectively. LHY746 exposures were not substantially changed in the presence of steady-state modafinil.

Conclusion: The results from this clinical study indicate modafinil 400 mg QD had a weak effect on encorafenib PK. Based on these results, encorafenib can be coadministered with a moderate CYP3A4 inducer without dosing adjustment.

Clinical trial registration: ClinicalTrials.gov NCT03864042, registered 6 March 2019.

Study objectives: TLD-1 is a novel pegylated liposomal doxorubicin (PLD) formulation aiming to optimise the PLD efficacy-toxicity ratio. We aimed to characterise TLD-1's population pharmacokinetics using non-compartmental analysis and nonlinear mixed-effects modelling.

Methods: The PK of TLD-1 was analysed by performing a non-compartmental analysis of longitudinal doxorubicin plasma concentration measurements obtained from a clinical trial in 30 patients with advanced solid tumours across a 4.5-fold dose range. Furthermore, a joint parent-metabolite PK model of doxorubicin_entrapped, doxorubicin_free, and metabolite doxorubicinol was developed. Interindividual and interoccasion variability around the typical PK parameters and potential covariates to explain parts of this variability were explored.

Results: Medians  $\pm$ standard deviations of dose-normalised doxorubicin_{entrapped+free} C_max and AUC_0-∞ were 0.342 $\pm$ 0.134 mg/L and 40.1 $\pm$ 18.9 mg·h/L, respectively. The median half-life (95 h) was 23.5 h longer than the half-life of currently marketed PLD. The novel joint parent-metabolite model comprised a one-compartment model with linear release (doxorubicin_entrapped), a two-compartment model with linear elimination (doxorubicin_free), and a one-compartment model with linear elimination for doxorubicinol. Body surface area on the volumes of distribution for free doxorubicin was the only significant covariate.

Conclusion: The population PK of TLD-1, including its release and main metabolite, were successfully characterised using non-compartmental and compartmental analyses. Based on its long half-life, TLD-1 presents a promising candidate for further clinical development. The PK characteristics form the basis to investigate TLD-1 exposure-response (i.e., clinical efficacy) and exposure-toxicity relationships in the future. Once such relationships have been established, the developed population PK model can be further used in model-informed precision dosing strategies.

Clinical trial registration: ClinicalTrials.gov-NCT03387917-January 2, 2018.

Purpose: To determine the bioavailability, safety, and tolerability of a single dose of oral docetaxel plus encequidar (oDox + E) and compare its pharmacokinetic exposure with current standard of care IV docetaxel.

Introduction: Docetaxel is a taxane widely used as an anti-neoplastic agent. Due to low oral bioavailability secondary to gut P-glycoprotein (P-gp) efflux, its current use is limited to intravenous administration. Oral docetaxel may provide a less resource intensive, more convenient, and tolerable alternative. Encequidar is a first in class, minimally absorbed, oral gut-specific P-gp inhibitor. We tested whether oDox + E can achieve comparable pharmacokinetic exposure to IV docetaxel.

Methods: A multicentre, phase I open-label, pharmacokinetic trial was undertaken to determine the bioavailability, safety, and tolerability of a single dose of oDox + E (at 75 mg/m2 + 15 mg, 150 mg/m2 + 15 mg, and 300 mg/m2 + 15 mg) in metastatic prostate cancer (mPC) patients compared to standard of care IV docetaxel as prescribed by their oncologists. The 15 mg of Encequidar at each dose level was given one hour prior to oral docetaxel.

Results: 11 patients were enrolled; 9 patients completed the study. Oral docetaxel exposure increased with dose, achieving the highest at 300 mg/m2 oDox + E (with AUC_{0 - infinity} of 1343.3 ± 443.0 ng.h/mL compared to the IV docetaxel AUC_{0 - infinity} of 2000 ± 325 ng.h/mL) and became non-linear at 300 mg/m². The mean absolute bioavailability of oDox + E across all 3 dose levels was 16.14% (range: 8.19-25.09%). No patient deaths, dose limiting toxicity, treatment-related serious adverse event or grade 4 toxicity were observed. Maximal tolerated dose was not reached.

Conclusion: oDox + E has a safe and tolerable adverse event profile in patients with metastatic prostate cancer. The increase in oral bioavailability of oDox + E suggests a multi-dose oDox + E regimen could theoretically achieve exposures comparable with standard of care IV docetaxel. Further development to examine the optimal multiple dose regimen of oDox + E is warranted.

Trial registration number: U1111-1173-5473.

Purpose: Quantifying the association of chemotherapy relative dose intensity (RDI) with overall survival may enable supportive care interventions that improve chemotherapy RDI to estimate their magnitude of potential clinical benefit.

Methods: This cohort study included 533 patients with stage II-III colon cancer who initiated a planned regimen of 12 cycles of 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX) chemotherapy. The primary exposure was chemotherapy RDI. The primary outcome was overall survival. Restricted cubic splines estimated hazard ratios (HR).

Results: Chemotherapy regimen RDI was associated with overall survival in an L-shaped pattern (linear P = 0.006; nonlinear P = 0.057); the risk of death was flat above 85% but increased linearly below 85%. For example, a decrease in RDI from 85 to 75% was associated with an increased risk of death [HR: 1.20 (95% CI: 1.08, 1.52)], whereas an increase in RDI from 85 to 95% was not associated with the risk of death [HR: 1.06 (95% CI: 0.82, 1.38)].

Conclusion: If chemotherapy RDI is considered a potential surrogate of overall survival, supportive care interventions that improve chemotherapy RDI might confer a potential clinical benefit in this population.

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a treatment-limiting and debilitating neurotoxicity of many commonly used anti-cancer agents, including paclitaxel. The objective of this study was to confirm the previously found inverse association between pre-treatment blood concentrations of histidine and CIPN occurrence and examine relationships of other amino acids with CIPN severity.

Methods: Pre-treatment serum concentrations of 20 amino acids were measured in the SWOG S0221 (NCT00070564) trial of patients with early-stage breast cancer receiving paclitaxel. The associations between amino acids and CIPN severity were tested in regression analysis adjusted for paclitaxel schedule, age, self-reported race, and body mass index with Bonferroni correction. The network of metabolic pathways of amino acids was analyzed using over-representation analysis. The partial correlation network of amino acids was evaluated using a debiased sparse partial correlation algorithm.

Results: In the primary analysis, histidine concentration was not associated with CIPN occurrence (odds ratio (OR) = 0.97 [0.83, 1.13], p = 0.72). In secondary analyses, higher concentrations of four amino acids, glutamate (β = 0.58 [0.23, 0.93], p = 0.001), phenylalanine (β = 0.54 [0.19, 0.89], p = 0.002), tyrosine (β = 0.57 [0.23, 0.91], p = 0.001), and valine (β = 0.58 [0.24, 0.92], p = 0.001) were associated with more severe CIPN, but none of these associations retained significance after adjustment. In the over-representation analysis, no amino acid metabolic pathways were significantly enriched (all FDR > 0.05). In the network of enriched pathways, glutamate metabolism had the highest centrality.

Conclusions: This analysis showed that pre-treatment serum amino acid concentrations are not strongly predictive of CIPN severity. Prospectively designed studies that assess non-amino acid metabolomics predictors are encouraged.